TI中文支持网Other Parts Discussed in Thread:TMS570LS3137
TMS570LS3137 的TRM的EMAC feature中提到八条接收发送channels支持接收发送QoS。但是在Code Generator的配置中显示只支持配置一个通道。
如果支持多个通道，那么在描述发送功能时，假如使能了4个发送通道，那么DMA如何选择向哪个通道发送数据？在描述接收功能时，假如使能了4个接收通道，DMA是如何选择接收哪个通道的数据？接收QoS是如何体现的？
Susan Yang：
Hardware QOS is enabled by the RXQOSEN bit in the receive multicast/broadcast/promiscuous channel enable register (RXMBPENABLE).
您可以看一下用户指南的
29.5.21 Receive Multicast/Broadcast/Promiscuous Channel Enable Register (RXMBPENABLE) 的 RXMULTEN
以及
29.2.11.4 Hardware Receive QOS Support
另外请您参考这个帖子
,
user6263934：
Q1。现在的HAL Code Generator中只可以配置使能某一个channel，那么EMAC确实是只能使用某一个配置的通道的？不存在使能多个通道的情况吗？
Q2。接收QoS，如何控制DMA去读哪一个通道？
Q3。发送QoS，如何控制DMA去向哪一个通道发送数据？
,
Susan Yang：
我在E2E发了帖子，您可以参考相关的回复
e2e.ti.com/…/3523333
Please refer to in the TRM: 32.2.11.4 Hardware Receive QOS Support
It looks like hardware ignores the ID portion of the tag, and just uses the priority bits (TCI = Traffic Class ID = priority bits), therefore we think that ID cannot be used in packet classification. Priority bits can be used to implement quality of service on receive where lower priority packets (TCI = 0 – 3 we think) will be dropped if there isn’t enough buffering available. Priority bits aren’t used to pick RX channel as far as we can tell.
,
Susan Yang：
请问您现在情况如何？以下是国外专家的回复原文：
It looks like hardware ignores the ID portion of the tag, and just uses the priority bits (TCI = Traffic Class ID = priority bits), therefore we think that ID cannot be used in packet classification. Priority bits can be used to implement quality of service on receive where lower priority packets (TCI = 0 – 3 we think) will be dropped if there isn’t enough buffering available. Priority bits aren’t used to pick RX channel as far as we can tell.
